InChrist wrote:Yes, I wanted to know if I can easily use Zoom, Teamviewer, Chrome with Firejail.

Also I am interested if I really need Firejail if I am not playing around.

I only use programs the mint software source 1 and 2 stable.

Plus Chrome, Google eartth, Zoom, Teamviewer or maybe other external programs where I will ask about security in this mint forum before deciding whether to install one.

It sounds as if you haven't fully grasped what Firejail is intended to protect you from or indeed what the risks are of using programs that directly or indirectly access untrusted files.

Examples of programs that directly access untrusted files are web browsers, chat programs, instant messengers, email clients, ftp clients, feed readers, podcast clients, twitch clients, or you name it any other program that doesn't work when you disconnect your computer from the Internet While your program may be trusted you should err on the side of caution and assume it will have bugs. Some of those bugs may be exploitable by malicious content. For example a bug in the image handler could be triggered by a specially crafted image file. When you visit a website that shows this image it could let to some code being executed on your computer that does something bad. Firejail limits what access your program has to your computer so the impact of such attacks is limited. Regardless of what you do on your computer, if you're using programs connected to the Internet you are at risk. Whether you consider that risk large enough to do something about it is up to you.

Similarly the above goes for programs that don't connect to the Internet. A likely example is downloading a PDF file and opening it with your PDF viewer. The PDF viewer doesn't access the Internet but in this way it does indirectly access untrusted files. Again, a specially crafted PDF file could exploit a bug in the PDF reader to have it execute some code that does bad things on your computer. Hence programs that don't connect to the Internet but do read files downloaded from the Internet can also benefit from using Firejail on them—it limits exposure to risks.

The examples you give are for closed source programs. In general I prefer to run closed source programs in Firejail for the additional reason that nobody but the program's authors can fix security issues. Nor can anybody see what shenanigans the program's authors were up to. Did they include a backdoor in their program? Is it gathering data about you and sending it home? While Firejail can't protect you from all of these threats it can at least ensure programs have limited access to the files on your computer (depends on the Firejail profile for the program what directories and files the program can and can't access).